Usual Adult Dose for Hypertension

Initial dose: 250 mg orally 2-3 times a day or 250 to 500 mg IV over 30 to 60 minutes every 6 hours, up to a maximum of 3 g/day.

Maintenance dose: 500 mg to 2 g orally divided in 2 to 4 doses, up to a maximum of 3 g/day.

Usual Adult Dose for Hypertensive Emergency

250 to 500 mg IV over 30 to 60 minutes every 6 hours up to a maximum of 1 g every 6 hours or 4 g/day. Switch to the oral route at the same dosage once blood pressure is under control.

Renal Dose Adjustments

CrCl < 15 mL/min: The dosage interval should be every 12 to 24 hours.

CrCl 15-50 mL/min: The dosage interval should be every 8 to 12 hours.

Liver Dose Adjustments

Methyldopa is contraindicated in patients with active hepatic disease, such as acute hepatitis and active cirrhosis.

Dose Adjustments

The daily dosage may be increased in intervals of not less than 2 days. Geriatric patients may require lower doses to minimize the risk of syncope.

Initiate treatment with lower doses if given concurrently with other antihypertensive agents.

Precautions

Following intravenous administration, the antihypertensive effect has an onset of 4 to 6 hours and a duration of 10 to 16 hours. Due to the slow onset of action, alternative therapy maybe indicated in serious situations.

Dialysis

Methyldopa is slightly dialyzable (5%-20%).